From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ie0-f180.google.com ([209.85.223.180]:35041 "EHLO mail-ie0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750811AbaEASDL (ORCPT ); Thu, 1 May 2014 14:03:11 -0400 Received: by mail-ie0-f180.google.com with SMTP id as1so3778175iec.25 for ; Thu, 01 May 2014 11:03:10 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <1398954948-24219-1-git-send-email-marcel.a@redhat.com> References: <1398954948-24219-1-git-send-email-marcel.a@redhat.com> From: Bjorn Helgaas Date: Thu, 1 May 2014 12:02:49 -0600 Message-ID: Subject: Re: [PATCH] PCI/shpchp: fix a bus speed issue on hotplug To: Marcel Apfelbaum Cc: "linux-pci@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Matthew Wilcox , "Michael S. Tsirkin" Content-Type: text/plain; charset=UTF-8 Sender: linux-pci-owner@vger.kernel.org List-ID: On Thu, May 1, 2014 at 8:35 AM, Marcel Apfelbaum wrote: > When a board is added, the shpchp driver checks if there > is a mismatch between the bridge's adapter and the bus speed. > If there is, it sets the subordinate speed (if there is no device on it). > > However, it takes the reference of the board speed from the primary bus > and not from the subordinate. If the primary bus is PCI and not PCIX/PCIe, > its speed is not updated and remains 0xff. As a result hotplug fails > with error: "Speed of bus ff and adapter 0 mismatch". It'd be cool to have a bugzilla for this with lspci and dmesg output. I'll also have to check the other hotplug drivers for similar issues, unless you've already done that. > Fixed that by checking the speed against the subordinate bus. > > Signed-off-by: Marcel Apfelbaum > Acked-by: Michael S. Tsirkin > --- > drivers/pci/hotplug/shpchp_ctrl.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c > index 5849927..6efc2ec 100644 > --- a/drivers/pci/hotplug/shpchp_ctrl.c > +++ b/drivers/pci/hotplug/shpchp_ctrl.c > @@ -282,8 +282,8 @@ static int board_added(struct slot *p_slot) > return WRONG_BUS_FREQUENCY; > } > > - bsp = ctrl->pci_dev->bus->cur_bus_speed; > - msp = ctrl->pci_dev->bus->max_bus_speed; > + bsp = ctrl->pci_dev->subordinate->cur_bus_speed; > + msp = ctrl->pci_dev->subordinate->max_bus_speed; > > /* Check if there are other slots or devices on the same bus */ > if (!list_empty(&ctrl->pci_dev->subordinate->devices)) > -- > 1.8.3.1 >